Attachment for disk-grinding machines.



F. N. & P. E. GARDNER. ATTACHMENT FOR DISK GRINDING MACHINES.

APPLICATION TILED JULY 26, 1910.

Patented Apr. 25, 1911.

2 SHBETB-BHEET 1 l zr/erzzar." axfw- M JIJW K514 a ma F. N. dz F. E.GARDNER. ATTACHMENT FOR DISK GRINDING MACEINBQ.

APPLICATION TILED JULY 20, 1010.

a (2M QWM Ja mvfizwz Patented Apr. 25, 1911.

UNITED STATESQPATENT OFFICE.

FREDERICK N. GARDNER AND FREDERIC E. GARDNER, 0F BELOIT, WISCONSIN, AS-SIGNORS OF ONE-THIRD TO LOUIS W'ALDO THOMPSON, OF BELOIT. WISCONSIN.

Application filed July 26,

To all who m it may concern:

Be it known that we, FREDERICK N. Gaun- Ma: and Fmcnnmo E. GARDNER,citizens of the United States residing at Beloit, in the county of Rockand State of Wisconsin, have invented certain new and usefulimprovements in Attaclunents 'tor .l)isk-(lriuding Machines, of whichthe following is a specification.

This invention contemplates an attach= ment for disk grinding machinesof the type disclosed in our copending application. Serial No. 528,791,filed November 18, moo. The machine shown in said application isespecially adapted for grinding or surfacing wood, and is particularlyintended for use by pattern makers.

The object of this invention is to provide an attachment for diskgrinders by means of which circular pieces of work of widely varyingdiameter may be quickly and accu- .rately finished or ground down to thede sired size.

In the accompanying drawings, Figure 1 is a fragment-a1 side elevationof a disk grinding machine having thereon an attachment embodying ourinvention. Fig. 9 is a fragmentary plan view showing the attachment anda portion of the machine in the position in which they appear in Fig."1. Fig. 3 is an'enlarged plan view of the attachment and fragment ofthe machine with the work table in a horizontal position. Fig. -t is asection taken in the plane of line t 4 of Fig. 3. Fig. 5 is a section online 5 5 of Fig. 4. Fig. (3 is a sectional view through a piece of work.Fig. 7 is a plan yiew of another piece of work. Figs. 8 and 9 areelevations of two forms of pins for mounting the work.

The machine illustrated in Fig. 1 comprises a suitable base 1 havingbearings 2 thereon in which is mounted a shaft 3 carrying a drive pulley1-. Fixed on one end of the shaft 3 is a disk 5, to the outer face ofwhich is secured a sheet of sand paper or other abrasive material. Asegment 6 having a. groove 7 therein is fixed to a member 8 which isvertically slidablo upon the base 1. Said member is attached to one endof a cable 9 passing over a sheave 10, the other end ot said cablecarrying a countel-balancing weight (not shown). The work t'able'll iscarried by a segment l2 having a curved rib on itsinner face whichtravels in the groove 7 in the segment (i. The segments (5 Specificationof Letters Patent.

1910. Serial No. 573,825.

ATTACHMENT FOR DISK-GRINDING MACHINES.

Patented Apr. 25, 1911.

and 1'. are secured together by meansoi bolts 13 passing through thesegment 6 and through areuate slots 14 in the segmentll, said boltshaving nuts 15 turned thereon.

It will be seen that the work table 11 may be titled either upwardly ordownwardly from a horizontal position into planes at various angles withthe disk 5. The inner edge of said table is beveled, as shown, to permitsuch tilting movement. The center of the are upon which the groove 7 isformed in a point which lies close to the abrading surface of the disk 5and coincides with the innermost portion of the beveled edge oi thetable 1.1. The movement of the segment 12 being a rotative one. and theaxis of rotation being coincident with the inner upper edge of the worktable, itwill be seen that the work table may be. tilted withoutchanging the position of the inner edge thereof. To clamp the table inthe desired position one of the nuts 15 may be turned up tightly bymeans of a handle 16 formed thereon.

()ur attzwhment'. in the form herein shown, comprises a bar 17 whichfits slidably in a groove 18 formed in the face of the work table 11parallel to the grinding disk 5. Fixed upon the bar 17 is a plate 19having a slot. extending tI-..1-ctln'oiigl1 at right angles to the bar17. In the present instance the plate 19 is formed in two duplicatepieces spaced apart on the bar 17 to form the slot 20. in the'slot 30,said bar having a plurality of holes 32 therein. The outer end oflthebar 21 has an angular lug 21$ thereon in which is threaded a stop screw21. said screw being arranged to engage the outer edge of the work table11 and limit the inward movement of the bar 21.

Tn Figs. 13 and 7, we have shown sample pieces of work which may beground Will! our attaelnnent. The work is mounted on the bar 21 by meanssuch. as a pin .25 (Fig. 9) the point ot'the pin being driven into thework and the head fitting closely but rotatably in one of the openings22 in the bar 21, as shown in Fig. 4. Another form of pin .26 is shownin Fig. 8. The head of this pin tits tightly into a recess a formed inthe block a (Fig. 6), the stem of the pin being adapted to enter one ofthe openings 22 in A bar 21 is slidably mounted thel ar 21, so thatthework may be rotated.

from very small to relatively large radius, the variation not dependingentirely upon the length of the adjusting or stop screw 24:.

The attachment is slidable in the groove 18 over the entire face of thegrinding disk 5. A This is very important in practice because it permitsof shifting the work for contact with different points along the face ofthe disk, or in other words, permits of shifting the cutting point.WVhen circular pieces of work are being ground, the cutting is confinedto a narrow space on the disk, and unless the work can be readily andfrequently-moved with reference to the disk, the abrading material inthis space becomes filled with tightly packed Wood dust, thus iialierially reducing the cutting action of the t is r.

In use, a pin 25 'or 26 is fixed in a pieceof work,'the 'slidable bar 21is drawn outwardly a short distance, and the pin fitted into one of theopenings 22, depending upon the size of the piece of work, When the stopscrew 24 has been set to limit inward movement of the bar 21 at theproper point, said bar is slid inwardly to carry the work against thegrinding d1sk 5. The workman may rotate the work with his fingers topresent its table'to move toward and away from the face of said disk;said member having an opening therein; a pin adapted to be fixed to thework and rotate in said opening so that the Workmay be rotated; andadjustable means for limiting the inward movement of said member.

2. In a disk grinding machine, the combi;

nation of a rotary grinding disk; a. work table supported adjacent tosaid disk; a bar slidably mounted on said table toimove toward and awayfrom said disk; said bar having an opening therein; a pin adapted to befixed to the work and rotate in said opening; and stop means carried bysaid bar and 1 adapted to limit the inward movement of Saidbar.

3. In a disk grinding machine, the combination of a rotary grindingdisk; a work table supported adjacent to said disk; a bar slidablymounted on said table to move to ward and away from said disk, said barhaving a series of holes therein; a pin adapted to be fixed to the workand rotate in one of said holes; and a stop screw carried by the outerend of said bar, said screw being arranged to engage the edge of theWork table for limiting inward movement of said bar 4:. In a diskgrinding machine, the combination of a rotary grinding disk; a worktable supported adjacent to said disk, said table having a groove in itsupper face parallel with said disk; a barfitting slid'ably in saidgroove; a plate fixed upon said bar and having a slot therethroughperpendicular to said bar; a second bar slidably mounted in said slot;said second bar having a longitudinal series of holes therein; a pinadapted to be fixed to the work and rotate in one of said holes; and anadjustable. stop screw carried by the outer end of said second bar, saidscrew being adapted to engage the outer edge of the work table forlimiting inward movement of said second bar.

5. In a disk grinding machine, the combinatioii of a rotary grindingdisk; a work table supported adjacent to said disk, said table havin agroove in its upper face parallel with said disk; a bar slidableinsaidgroove over substantially .the entire face of said disk; a membermounted on. said bar tQ'fslide toward and away from said disk;

inc-ans for forming a" rotatable connection between said member and apiece of work; and adjustable means for limiting the inward movement ofsaid member.

FREDERICK N. GARDNER.

FREDERIG E. GARDNER.

l/Vitnesses:

II. M, ADAMS, CARRIE HIoKsoN.

